Safety operating mechanism



H. DE SMITH.

SAFETY UPERATING MECHANISM.

APPLlcAnoN mw JULY 2a. |916.

1,280,971 Patented 0c. 1918.

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, n ve Toi H. DE SMITH.

SAFETY OPERATING MECHANISM.

APPLICATION FILED IULY 28.1916.

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HENRY DE SMITH, OF ROCHESTER, NEW YORK, ASSIGNOR T0 M. D. KNOW'LTON COM- IPANY, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

SAFETY OPERATING MECHANISM.

-Specification of Letters Patent.

Patented Oct. 8, 1918.

Application led July l28, 1916. Serial N o. 111,769.

T0 all 'whom t may concern:

y ating means to the work-performing element only when the latter is in close proximity to the work to be operated upon. At all other times, the work-performing element will yield if it meets with an obstruction, such as the operators hand, and, therefore, no harm will be done. t

The object of this invention is to provide a safety device or safety operating mechanism of'this kind having the improvement hereinafter set forth. i

The invention is illustrated in the accompanying drawings, which show the safety operating mechanism applied to a box-staying machine. but it will be obvious that it may be used on other types of machines as well. f

In the drawings Figure l is a'front elevation of a portion vof a box staying machine, certain parts be- ,I ing broken away to show the safety operatino mechanism; v

Fig. 2 1s an-enlarged view of the safety operating mechanism showlng the parts in the position which they assume just prior to the engagement of the work by the workperforming element; v

Fig. 3 is a vertical section taken on the line 3-3 of Fig. 2; and

Figs. 4 and 5 are end and side views respectively, of a springforming part of the safety operating mechanism, the view of the spring in Fig. 5 being on a larger scale than that in Fig. 4:.

The box staying machine illustrated in the drawings is of the usual construction, and comprises a movable die A and a stationarydie or anvil B. The movable die A is carried by a reciprocating slide C provided` with a rearwardly projecting pin D. y

stance, is provided with a crank pin F. The 5 crank pin F is connected with the pin D by a link or pitman construction, which is constructed in the manner hereinafter described, to constitute the safety device or safety operating mechanism hereinbefore referred to.

The safety operating mechanism or safety link comprises two power transmitting elements, one of which is indicated at 1, and is journaled on the crank pin F, and the other is shown at 2, and is pivotally connected with the pin D. A bushing 3 may be interposed between the pin F and the part 1, and a similar bushing 4 interposed between the pin D and the part 2.

The depending power transmitting ele ment 1 has a bifurcated lower extremity forming an elongated opening 5, in which the pin D engages and in which it is freely slidable. The parts 1 and 2 are connected by means of a pin 6 secured in the part 2 and engaging in an opening 7 in the part 1, preferably having the shape shown in Fig 2. An enlarged head 8 on the pin 6 overlies the face of the part 1, and serves to hold the parts 1 and 2 together.

The depending power transmitting element 1 is provided with a shoulder 9, which is adapted to engage with a corresponding shoulder 10 formed on the power transmitting element 2. The parts are held in the position shown in Fig. 2, in which the shoulders 9 and 10 are in engaging relation, by means of a spring 11, having one or more eonvolutions wound around the hub of part 2, and having one of its extremities secured to the part 1 and the other extremity secured to the part 2, so that the part 2 will normally be held in the position shown in Fig. 2. A suitable stop 12 may be provided for limiting the movement of the part 2.

An extension of the pin F is formed into a cam 13. and is so shaped that just after the movable die A leaves the work on the up stroke of the safety link. the part 2 will be shifted to the position shown in Fig. 1, in which the shoulders 9 and 10 are out of engaging relation. The cam 13 holds the part 2 in this position during 4the up and down, stroke of the link until the movable die A, or work-performing element, is about of an inch from the work to be operated upon. At this time, the cam assumes the position shown in Fig. 2, and permits the spring 11 to shift the part 2 to the position shown in Fig. 2. The shoulders 9 and 10 are then in engaging relation, and pressure transmitted from the crank pinF through the parts 1 and 2 to the pin D, the same as if a solid link were providedbetween the pins F and D.

lf the worl -perforlning element, which,

inthe present instance, is the movable die A, encounters any obstacle during its downward movement, such as the operator-s hand, the parts l and 2 will yield or move relative to each other, since the pin D and part 2 will beheld stationary by the obstacle, and as the shoulders 9 and 10 vare not in `engaging relation, the part 1 andY crank pin' F willv parts move relative to each other, as just described, the upper extremity of the `part 2 will be thrown to one side of thel cam" 13, and the cam in Vdescending will move ddwnward relative to ythe 'upper end of Vthe vpart 2, in an obvious manner.

Obviously, any Obstruction .over r2; Qi all inch in thickness will cause 'the'partsto collapse or` move relative to each other, as above v cl'escribed,'since the shoulders`9 and 10 are not inengaging relation at lany time, until the work-performingy element is of "an Vinch from the work to be operated upon. When the shoulders 9 and 10 Eare engaging relation, v11o/pressure will`be. applied to the obstacle under the work-perforniing element, and, therefore, the operators hand, if accidentally .Caught between the dies, y,will be,i1i1i1iure.d

AS hereilibefore described, the, link Parts.

1 and 2 are held with their shoulders ,9 and l0 @iii Qf engaging relation "duties the fui) stroke of the link and also during the down stroke vof the .saine until the Idie A is about Jg of Van inch from the work to be 'operated upon. During'such down stroke of vthg'a'link, the part V1 and 2,- ymay be held ,against collapsing-such as would occur if the lower part and connecting die Adid not InOVe 'as fast as the upper part and its connecting pin Ffby the frictional ,engagement between the parts obtained by the headed pin 'or screw 6. It hasV been found in practice, however, that Vsonne other y or additional means is desirable for holding Ythe said linkY parts against collapsing, that will automatically provide for 'any wear 4or vloo'sei'iing of the parts. I have therefore Aprovided a means for .yieldingly holding the two link parts in such frictional engagement as will suliice to hold them against collapsing during the down stroke and at the same time permit of the described relative sliding movements of the .parts in shifting to their operative and inoperative positions'. Such means may be any sui-table for the purpose, but a preferred means comprises the spring 11 whichis here formed with its coiled .portion expanding between the adjacent ends 'of 'the lin-k parts 1 and v2 to produce the necessary friction between said parts uas they slide over one another and under t-he head ofthe -pfif'nl or screw 46 which cofnects them.'

` 'A springfsimila'r to ythe spring 11 here shown "disclosed'in the pending l'application "of Edgar M.V Hawkins, Serial *No 862,480, but-that spring lis formed ywith, tig-ht coils, that is, theJ adjacent coils ofthe wire in contact with one another, `this being done because the functionof "the spring is simply that' of normally holding the linkl parts in 'their operative position Ywith fthe Y shoulders 9 and 10 in'e'n'gaging relation. The A'spring '11' here shown, nlliowever, `'is formed' with open'coils, as 'shown in 5. Thus when the link is assembled, tles'ecils are brought iinder compressin sidewise `'or in la direetion parallel to thefaXis v'of 'the coil, whereby they will" aa, to 'produce "the aesired friction between the as 'described. The s therefore performs the function of yt e similar spring-of thel aforesaid pending application, plns the additional function of @collapsing of the link parts.

1.` In a machine 'of the kind Specified, the @Onbeafiidii with iii@ eiiiis means-iisd the worlcperforrning element, of `a safety link connecting the saine and comprising two parte @really heldin an iiiiteifaiiive Positieii Yfor transmitting ,pwei d 011e Y beine ,laiefalllv Slidbl o'n the ether,

matic means for shifting thegp'ositiofn of xone of the parts to VVpermit said partsto contact @ed ieiildei' the sem @festive .frireiemii- .tins newer juist piieiitlie engagement of the Work by the workperforming 'element and means yieldin'gly ,holdingy sad parts in frictiollal engagement with 1each 'other and against 'collapsingwhen in ytheir said inoperative position. i

2'- in, i maffia@ @if the kind speen-ed, ,the @Ombination 'with the ,actuating means @iid the wellifperforming einen,it.v of a is rey link connecting th'e same and comprising two. Parts. normally held iii an inopeef've Position for, transmitting power] and, one being laftially slidable '011i the other; automatic means fer shifting the @einen of 'one Of the 'rafts f6 Permit said Parts to @infect and render the saine einective fortr'ansinit- 2111s p'OWLi prrteth 'engagement 0f the work by the wdrk-'performing element, and a spring 'yieidinglyjholding said parte 1n frictional engagement with each other and against collapsing when in their said inoperative position.

3. In a machine of the kind specilied, the 'combination With the actuating means and the Work-performing element, of a safety link connecting the same and comprising two parts normally held in an inoperative position for transmitting; power and one belng laterally slidable on the other, and a spring for shifting the position of one or'.

the arts to permit said parts to contact and ren er the same effective for transmitting power just prior to the engagement of the work by the Work-performing element, said spring being constructed and operative to also yieldingly hold the link parts in l'rictional engagement with each other and against collapsing when in their said inoperative position.

4. In a machine of the kind specified, the combination with the actuating means and a vertically reciprocating work-performing element, of a safety link connecting the same and comprising two parts provided with shoulders adapted to engage when said parts are in their operative positions and one of said parts being laterally slidable on and relative to the other, and means controlling the lateral movement oi said slidable part so that the said shoulders of the parts will automatically engage at a predetermined point duringthe down stroke of the link and just prior to the engagement ofthe work by the work-performing element, said controlling means comprising a spring which is constructed and operative to also yieldingly hold the link parts in frictional engagement with each other and against collapsing during the down stroke ofthe link prior to the engagement of the link shoulders.

Signed at Rochester, in the county of Monroe, and State of New York, this 25th day of July A. D. 1916.

HENRY DE SMITH.

Witnesses TI-Ios. D. PA'rToN, CEoIL H. FEARNLEY.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

